GLAPI/glVertexAttribFormat

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glVertexAttribFormat
Core in version 4.4
Core since version 4.3
Core ARB extension ARB_vertex_attrib_binding

glVertexAttribFormat: specify the organization of vertex arrays

Function Definition

 void glVertexAttribFormat(GLuint attribindex​, GLint size​, GLenum type​, GLboolean normalized​, GLuint relativeoffset​);
 void glVertexAttribIFormat(GLuint attribindex​, GLint size​, GLenum type​, GLuint relativeoffset​);
 void glVertexAttribLFormat(GLuint attribindex​, GLint size​, GLenum type​, GLuint relativeoffset​);
attribindex
The generic vertex attribute array being described.
size
The number of values per vertex that are stored in the array.
type
The type of the data stored in the array.
normalized
GL_TRUE​ if the parameter represents a normalized integer (type​ must be an integer type). GL_FALSE​ otherwise.
relativeoffset
The offset, measured in basic machine units of the first element relative to the start of the vertex buffer binding this attribute fetches from.

Description

glVertexAttribFormat, glVertexAttribIFormat and glVertexAttribLFormat specify the organization of data in vertex arrays. attribindex​ specifies the index of the generic vertex attribute array whose data layout is being described, and must be less than the value of GL_MAX_VERTEX_ATTRIBS​.

size​ determines the number of components per vertex are allocated to the specifed attribute and must be 1, 2, 3 or 4. type​ indicates the type of the data. If type​ is one of GL_BYTE​, GL_SHORT​, GL_INT​, GL_FIXED​, GL_FLOAT​, GL_HALF_FLOAT​, and GL_DOUBLE​ indicate types GLbyte​, GLshort​, GLint​, GLfixed​, GLfloat​, GLhalf​, and GLdouble​, respectively; the values GL_UNSIGNED_BYTE​, GL_UNSIGNED_SHORT​, and GL_UNSIGNED_INT​ indicate types GLubyte​, GLushort​, and GLuint​, respectively; the values GL_INT_2_10_10_10_REV​ and GL_UNSIGNED_INT_2_10_10_10_REV​ indicating respectively four signed or unsigned elements packed into a single GLuint​; and the value GL_UNSIGNED_INT_10F_11F_11F_REV​ indicating three floating point values packed into a single GLuint​.

glVertexAttribLFormat is used to specify layout for data associated with a generic attribute variable declared as 64-bit double precision components. For glVertexAttribLFormat, type​ must be GL_DOUBLE​. In contrast to glVertexAttribFormat, which will cause data declared as GL_DOUBLE​ to be converted to 32-bit representation, glVertexAttribLFormat causes such data to be left in its natural, 64-bit representation.

For glVertexAttribFormat, if normalized​ is GL_TRUE​, then integer data is normalized to the range [-1, 1] or [0, 1] if it is signed or unsigned, respectively. If noramlized​ is GL_FALSE​ then integer data is directly converted to floating point.

relativeoffset​ is the offset, measured in basic machine units of the first element relative to the start of the vertex buffer binding this attribute fetches from.

glVertexAttribFormat should be used to describe vertex attribute layout for floating-point vertex attributes, glVertexAttribIFormat should be used to describe vertex attribute layout for integer vertex attribute and glVertexAttribLFormat should be used to describe the layout for 64-bit vertex attributes. Data for an array specified by glVertexAttribIFormat will always be left as integer values; such data are referred to as pure integers.

Notes

GL_UNSIGNED_INT_10F_11F_11F_REV​ is accepted for type​ only if the GL version is 4.4 or higher.

Errors

GL_INVAILD_VALUE​ is generated if attribindex​ is greater than or equal to the value of GL_MAX_VERTEX_ATTRIBS​.

GL_INVALID_VALUE​ is generated if size​ is not one of the accepted values.

GL_INVALID_VALUE​ is generated if relativeoffset​ is greater than the value of GL_MAX_VERTEX_ATTRIB_RELATIVE_OFFSET​.

GL_INVALID_ENUM​ is generated if type​ is not one of the accepted tokens.

GL_INVALID_OPERATION​ is generated if no vertex array object is bound.

Associated Gets

glGet with arguments GL_MAX_VERTEX_ATTRIB_BINDINGS​, or GL_MAX_VERTEX_ATTRIB_RELATIVE_OFFSET​.

glGetVertexAttrib with argument GL_VERTEX_ATTRIB_RELATIVE_OFFSET​.

See Also

glBindVertexArray, glEnableVertexAttribArray, glVertexAttribBinding, glVertexAttribPointer, glVertexBindingDivisor

Copyright

Copyright © 2012 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.